Refrigerating apparatus



y 1958 w. K. STEINHAGEN ET AL 2,835,436

' REFRIGERATING APPARATUS Filed April 8. 1953 4 Sheets-Sheet 1 Fig. l-

D no T g 26 ii a/zljollzllz "m n 100 I4 JNVENTOR. Wil/iamKSfeinhagenJohn 00/20 and Philip L. Francis Q. J.

Their Attorney.

May 20, 1958 w. K. STEINHAGEN ET AL 2,835,436

REFRIGERATING APPARATUS Filed April 8. 1953 4 Sheets-Sheet 2 TheirAttorney.

y 0, 1958 w. K. STEINHAGEN ET AL 2,835,436

REFRIGERATING APPARATUS Filed April 8. 1953 4 Sheets-Sheet 3 INVENTOR.

WiIliamKSteinhagen John 00/20 and Philip L. Franc/s By W fheir Atfornev.

w/k. STEINHAGEN ET AL 2,835,436

May 20, 1958 REFRIGERATING APPARATUS 4 Sheets-sheaf, 4

Filed April 8. 1953 JNVENTOR. William K Sfeinhagen John Dolza and PhilipL. Francis f8. 02.,

Their Attorney.

,- REFRIGERATING APPARATUS William K. Steinhagen, Royal Oak, John Dolza,pavisburg, and Philip L. Francis, Pontiac, Mich, asslgnors to GeneralMotors Corporation, Detroit, Micln, a corporation of DelawareApplication April 8, 1953, Serial No. 347,556

4 Claims. (Cl. 230-486) the compression chamber to be relieved withoutinjuryto the valves. 7

Still another object of this invention is to provide an improved oilingarrangement capable of supplying lubricant to all parts of thecompressor.

Another object of this invention is to provide a cornpressor suitablefor use with an automobile air conditioning system wherein thecompressor is required to operate at widely varying speeds.

Further objects and advantages of the present invention will be apparentfrom the following description, reference being had to the accompanyingdrawings, where in a preferred form of the present invention is clearlyshown.

In the drawings:

Figure l is an elevational view with parts broken away showing apreferred embodiment of the invention;

Figure 2 is an end elevational view showing the refrigerant inlet andoutlet connections;

Figure 3 is a sectional view taken substantially on line 33 of Figure 2;

Figure 4 is a sectional view taken substantially on line 4- l of Figure3;

Figure 5 is a fragmentary sectional view taken substantially on line 5-5of Figure 4;

Figure 6 is a sectional view taken substantially on line 6--6 of Figure3;

Figure 7 is a sectional view with parts broken away taken substantiallyon line 7-7 of Figure 3;

Figure 8 is a fragmentary sectional view of a guide shoe and is takensubstantially on line 8-8 of Figure 3; and,

Figure 2 is a sectional view taken on line 9--9 of Figure 8.

For purposes of description the pump will be referred to as arefrigerant compressor whereas certain aspects of the invention areequally applicable to pumps used for other purposes. Referring now tothe drawing wherein a preferred embodiment of the invention is shown,reference numerals 10, 12 and 14 designate the crankcase, cylinder blockand cylinder head respectively of the compressor. Reference numeral 16designates a two piece main drive shaft which has secured thereto adrive pulley 18 adjacent its one end. The pulley 18 is adapted to bedriven through the belt 20 from the main crankshaft of car engine (notshown) or any other suitable source of power. The pulley 18 is keyed tothe shaft 16 by means of a conventional key 22 and is held in place onthe shaft by means of the usual cap screw and washer assembly 24. r Aball bearing assembly 26 supported within the one end of the crankcase10 serves to rotatably support the one end of the drive shaft 16.

An end bell 28 is secured to the one end of the crankcase and serves tosupport a conventional shaft seal assembly 34 and an oil pump retainingplate 32. A gear type of oil pump is mounted between the plate 32 andthe end wall of the crankcase and comprises a first pumping gear 34keyed to the main compressor drive shaft 126 and a complementary pumpinggear 36 journaled on a stud 38 carried by the end wall of the crankcaseIll as best shown in Figures 4 and 5.

The lower portion of the crankcase 10 serves as an oil sump for a bodyof oil 40 from whence the oil pump withdraws oil through the inletpassage 42 (see Figures 1 and 4). The oil leaves the gear pump throughthe outlet port 44 which communicates through an aligned opening inplate 32 (not shown) with the cavity 46 in which the shaft seal 30 ismounted so as to build up oil pressure within the shaft seal cavity.

The amount of pressure which is allowed to build up in the shaft sealcavity 46 is limited by a spring loaded safety valve 43 (see Figure 5)mounted between the retaining plate 32 and the end wall of the crankcaselit. The valve 48 is so calibrated that when the pressure within thechamber 46 exceeds a desired value, the valve will open so as to allowexcess lubricant to return to the crankcase 10 through the passage 50.

A hearing sleeve 52 is keyed to the shaft 16 by means of a pin 54 whichalso keys the oil pump gear 34 to the shaft. The sleeve 52 is providedwith an oil passage 56 (see Figures 1 and 3) which is in alignment witha radially extending oil passage 58 provided in the shaft 16. Theradially extending passage 58 communicates with an axially extending oilfeed passage 68 provided in the main drive shaft 16 whereby oil underpressure which discharges from the oil pump is delivered to the oilsupply passages 60 in the drive shaft 16. The central portion of driveshaft 16 is provided with an offset crank portion so which serves todrive a wobble plate assembly 68 as best shown in Figure 3. The wobbleplate assembly 63 is provided with a plurality of sockets 7t) whichreceive the spherical ends of the connecting rods 72.

For purposes of illustrating this invention, a compressor having fivecylinders has been shown whereas the number of cylinders may be variedwithout departing from the spirit of my invention. The wobble plateassembly 68 is provided with five of the sockets '70 for receiving theends of five connecting rods like the connecting rod 72 which is visiblein Figure 3. The free ends of each of the connecting rods 72 areprovided with spherical portions as shown. Pistons Sti having socketlikeformations 82 engage the one end of each connecting rod '72.. Thepistons 8t? operate within compression chambers or cylinders provided inthe cylinder block 12 whereby upon rotation of the shaft 16 the wobbleplate so will cause reciprocation of the pistons 8% within thecompression chambers 84.

The wobble plate 63 is prevented from rotating by means of a shoeassembly 99 which projects from one side of the wobble plate 68 andslides within a slot 92 provided in one wall of the crankcase it) asbest shown in Figure 3. The shoe ssembly 99 is best shown in Figures 8and 9 and consists of a pair of guide shoe elements 94 and 96 which arekeyed loosely together by means of a key 98 so as to allow the guideshoe elements 94 and 96 to adjust themselves within the guide slot 92.

A valve plate 100 is provided adjacent the head end of the cylinderblock 12 and is provided with a common central inlet port 111 whichserves all of the cylinders 3 and a plurality of outlet ports 102through which the compressed refrigerant discharges into the circularoutlet chamber 104 provided in the cylinder head 14] The compressedrefrigerant leaves the chamber 104 through the discharge line 105.Suitable outlet valves 106 have been provided adjacent each of theoutlets 102 in accordance with conventional practice. For purposes ofillustration reed type outlet valves have been shown Whereas any type ofvalve could be used insofar as certain aspects of the invention areconcerned.

The refrigerant to be compressed enters through the suction line 108which leads to a central inlet cavity 110 also provided in the cylinderhead 14. An impeller 112 supported adjacent the one end of the maindrive shaft 16 serves to separate some of the incoming oil from therefrigerant vapor by means of the centrifugal action of the rotatingimpeller 112 on the oil.

The flow of low pressure gas from the chamber 110 into the variouscompression chambers 84 is controlled by a rotating valve element 116which is splined to the drive shaft 16 so as to rotate in unison withthe drive shaft while being free to slide axially on the drive shaft fora purpose to be explained hereinafter. As best shown in Figure 7, thevalve plate 116 is provided with a pair of ports 118 which allow therefrigerant to be compressed to enter the various compression chambers84 during the respective suction strokes of the pistons 80. As bestshown in Figures 3 and 7 a portion of the valve element 116 is cut awayas at 120 whereby the ports 118 communicate with more than one of thecompression chambers at the time. The relative position of the valveelement 116 on the drive shaft 16 is such that the low pressure gas orrefrigerant is only admitted to the cylinders during the suction stroke.The valve 116 normally prevents the escape of compressed gas from eachof the compression chambers during the compression stroke. However, inthe event that any liquid slugs should enter any of the cylinders so asto produce excessive pressures within one or more of the cylinders suchexcessive pressure would be suflicient to move the valve element 116against the force of the retaining spring 122 so as to relieve suchexcessive pressure. It will be observed that such movement of the valveelement 116 serves to connect all of the cylinders 84 together andthereby completely unload the compressor until such a time as the liquidslug condition has been relieved at which time the valve element 116will again move into sliding engagement with the end wall of thecylinder block.

A bearing insert 130 serves to support the shaft 16 within the cylinderblock 12. Radial oil feed passages 132 have been provided for feedingoil from the main oil passage 60 to the bearings 130. An oil feedpassage 134 serves to feed oil to the wobble plate bearing assembly 136and to the sockets 70 as well as the guide shoe assembly 90. As shown inFigure 1 of the drawing, oil separated out from the incoming lowpressure gas by means of the impeller 112 is free to return to the mainoil sump 40 through the oil return passage 138. Excess oil escaping fromthe bearing 130 may also return to the oil sump 40 through the oilreturn passage 140. Whereas only one oil passage 140 shows in Figure 1,additional passages 142 similar to the passage 140 are provided as shownin Figure 6 so as to allow for equalization of pressures within thecrankcase and the chamber 144. It will also be noted that the right-handend of the shaft 16 as viewed in Figure 3 is provided with passage means146 connecting the chamber 144 with the inlet chamber 110. A felt washer148 has been provided as shown in Figure 3 so as to prevent the oilwhich enters the chamber 144 from returning to the inlet side of thecompressor. As shown in Figure 3, oil for the main bearing assembly 26is supplied thereto directly from the shaft seal cavity 46 through theoil feed passage 150 formed in the plate 32 and the end wall of thecrankcase 10.

While the form of embodiment of the. invention as herein disclosedconstitutes a preferred form, it is to be understood that other formsmight be adopted, as may come within the scope of the claims whichfollow.

What is claimed is as follows:

1. In a refrigerant compressor or the like, means forming a crankcaseadapted to contain lubricant, a main drive shaft projecting through onewall of said crankcase, bearing means for said shaft, a cylinder blockhaving a plurality of compression chambers circumferentially arrangedrelative to said shaft, piston means operated by said shaft within saidchambers, a cylinder head and valve plate assembly closing the ends ofsaid compression chambers, said valve plate including a plurality ofports co'mmunicating with said chambers, valve means for said ports,said cylinder head cooperating with said valve plate to form a dischargechamber and a suction chamber each communicating with each of saidcompression chambers through said ports, means forming a passageconnecting said crankcase to said suction chamber whereby the pressurein said crankcase is substantially equal to the suction pressure, andpump means operated by said shaft and having an inlet communicating withlubricant in said crankcase, said pump having an outlet for discharginglubricant under pressure to said bearing means.

2. In a multiple cylinder wobble plate compressor, a casing'formingan'oilsump, a cylinder block adjacent one end of said casing andprovided with a plurality of cylinder bores having their ends exposedwithin said oil sump, a stationary valve plate secured to one end ofsaid cylinder block and provided with a plurality of inlet and outletport means communicating with said cylinder bores, individual valvemeans for said outlet ports, a main drive shaft having one endjournalled in said cylinder block and having its other end journalled inone wall of said casing, a wobble plate supported on and operated bysaid shaft, a plurality of pistons operable within said bores,connecting rods connecting said pistons and said wobble plate, acylinder head arranged in abutting relationship to said valve plate andhavinga first chamber communicating with said inlet port means and asecond chamber communicating with said outlet port means, and meansforming a passage connecting said oil sump to said first chamber.

3. In a multiple cylinder wobble plate compressor, a casing forming anoil sump, a cylinder block adjacent one end of said casing and providedwith a plurality of cylinder bores having their ends exposed within saidoil sump, a stationary valve plate secured to one end of said cylinderblock and provided with a plurality of inlet and outlet port meanscommunicating with said cylinder bores, individual valve means for saidoutlet ports, a main drive shaft having one end journalled in saidcylinder block and having its other end journalled in one wall of saidcasing, a wobble plate supported on and operated by said shaft, aplurality of pistons operable within said bores, connecting rodsconnecting said pistons and said wobble plate, a cylinder head arrangedin abutting relationship to said valve plate and having a first chambercommunicating with said inlet port means and a second chambercommunicating with said outlet port means, and means forming a passageconnecting said oil sump to said first chamber, said cylinder headcomprising an one-piece casting having inlet and outlet apertures forthe fluid to be compressed.

4. In a multiple cylinder wobble plate compressor, a casing forming anoil sump, a cylinder block adjacent one end of said casing and providedwith a plurality of cylinder bores, a stationary valve plate secured toone end of said cylinder block and provided with a plurality of inletand outlet ports, individual valve means for said outlet ports, a maindrive shaft having one end journalled in said cylinder block and havingits other end journalled in one wall of said casing, a wobble platesupported on and operated by said shaft, a plurality of pistons operablewithin said bores, connecting rods connecting said .pistons and saidwobble plate, a cylinder head arranged in abutting relationship to saidvalve plate and having a first chamber communicating with said inletports and a second chamber communicating With said outlet ports, andmeans forming a passage connecting said oil sump 5 to said firstchamber, said cylinder head comprising a one-piece casting having inletand outlet apertures formed therein for the fluid to be compressed, saidsecond chamher being arranged so as to substantially surround said firstchamber. 10

References Cited in the file of this patent UNITED STATES PATENTS1,416,731 Martin May 23, 1922 15 6 Pick Oct. 8, Erling July 14, WoodsJan. 5, Dick July 6, Beeh July 31, Cowles Oct. 21, Stoyke Jan. 31,Cardillo Nov. 6, Floraday July 2,

FOREIGN PATENTS Switzerland July 15,

